Pesticides can’t be blamed for the mysterious mass die-off of honeybees that several Ohio
beekeepers reported in April, according to the Ohio Department of Agriculture.

The department tested samples of dead bees and ran the results against a database of 300
pesticides.

“It came back negative,” Brett Gates, an agency spokesman, said yesterday. “No pesticides were
detected in them.”

Many beekeepers suspected that a class of insecticides called neonicotinoids were to blame for
the piles of dead bees they discovered outside their hives that month. Neonicotinoids are used to
coat seed corn and have been linked to bee deaths in other states and countries.

In January, a Purdue University study found “extremely high levels” of the insecticide in talc,
a powder used to help spread the corn seeds across fields. The study found that the greatest
potential exposure to bees occurred when waste talc was released in planting-machinery exhaust.

Beekeepers and an Ohio State University honeybee expert said the manner in which the Ohio bees
died was suggestive of pesticide poisoning.

The agriculture department’s finding surprised John George, the vice president of the Ohio State
Beekeepers Association.